Method of and means for recording signals electrically



Nov. 28, 1939. B. L. KLINE El AL 1 5 METHOD OF AND MEANS FOR RECORDING SIGNALS ELECTRICALLY Filed Jan. 18, 1956 FIG.4

R.D.PARROTT i smcKsow A N Y INVENTORS B.L.KLI NE Patented Nov. 28, 1939 UNITED STATES PATENT OFFICE METHOD OF ANDlVIEANS FOB RECORDING SIGNALS ELECTRICALLY Application January 18, 1936, Serial No. 59,780

9 Claims.

The present invention relates to methods of and means for producing visible marks on a record surface and more particularly to novel methods of and means for reception of facsimile and picture records over communication channels.

Telegraphic receiving papers of the prior art which cannot be used dry but must be substantially saturated with water prior to use are unsatisfactory for the reason that the surface fibres separate from the body of the paper and tend to" interfere with the recording instrumentality and they do not dry readily. Receiving apparatus designed for use with these prior art wet papers are equipped with special arrangements for wetting the paper and also for handling the paper in the wet condition after application of the water. Recording blanks produced in accordance with the present invention are entirely free of the above enumerated and other disadvantages attending the use of previously known moist recording blanks.

In accordance with the present invention, a sheet or layer of paper or other fibrous material is coated, impregnated or otherwise supplied with a color changing medium and, if necessary, a substance which becomes conductive when moistened with a non-aqueous volatile solvent. The dry electrolytes, of which .examples are given hereinafter, may be applied to the sheet either in the dry state by coating, or in the wet state by impregnating the sheet with a solution and subsequently drying, or it may be applied in solution in the volatile solvent when the sheet is used for recording. Accordingly; a ma' jor object of the present invention is to provide a novel telegraphic recording blank which is conditioned for use by moistening with a nonaqueous volatile solvent.

A further object of the invention is to provide novel recording means to permit use of greatly simplified recording apparatus of the type employing a moistening device for the record sheet.

Another object of the present invention resides in the provision of novel moistening means for a record blank in telegraphic and like recording apparatus.

Still another object is to provide a recording blank adapted to be moistened within successive areas of limited extent as recording proceeds.

The foregoing and more specific objects will appear in the following complete disclosure of the invention in its several aspects.

Referring to the drawing:

Fig. 1 is a view in side elevation of cooperating parts of a recorder suitable for use in practicing the present invention;

Fig. 2 is a view similar to Fig. 1 illustrating a modification;

'Fig. '3 is a side elevational view of a continuous type of recorder embodying the present invention in a modified form;

Fig. 14 is a plan view partly in section of the apparatus disclosed by Fig. 3;

Fig. 5 is an enlarged section taken on the line 55 oi Fig. 4; and

Fig. 6 is a perspective view of a receiving blank embodying the present invention, the thickness thereof being exaggerated for the sake of clearness.

Referring for the present to Fig. 1 of the drawing, reference character l denotes 9. cylinder which is adapted to receive a record blank in contact with its periphery. The cylinder It) is supported and rotated in any suitable manner, for example, by the means disclosed in the application of Raleigh J. Wise et al., Ser. No. 23,927, filed May 28, 1935. A recording stylus II is supported upon a member l2 preferably of insulating material, and the member l2 in turn is supported upon a carriage 14. The carriage [4 slides along a guide I5 and is preferably pivoted to the guide so as to permit the stylus H to be readily raised when it is desired to interrupt the recording operation. The carriage I4 is provided with an internally threaded member IE which is engaged over a threaded shaft ll, the latter being driven from the cylinder Ill. The guide l5 and the threaded rod I'l are so positioned with respect to each other that When the stylus II is raised from the surface of the cylinder ID, the driving action of the threaded rod I! on the member l6 supported thereby is interrupted, arresting advance of the carriage l4. Secured upon the. carriage I4 is a bracket 20 which is provided with a lateral extension serving to receive and position a conduit 2|, the free end of the conduit being supported adjacent the periphery of cylinder Ill. Inserted in the end of the conduit 2| is a block 22 of suitable absorbent material such as felt, which serves to moisten the surfaces of the blank as the cylinder I0 is rotated. The conduit 2| is in communication with a suitable reservoir 24 which is carried by or rests upona band 26 secured to the bracket 20. It will be understood that the recording device comprising the cylinder l0, car.- riage I4 and the supporting and the driving devices for the carriage may be of any suitable or desired structure. A receiver of the type in which the cylinder itself is advanced axially past a fixed recording device may be used. I

The recording blank 28 disclosed in Fig. 6 of the drawing may be of a form suitable for application to the cylinder III or it may be a continuous sheet or web useful in an apparatus of the type disclosed in Fig. 3'. This blank comprises a body portion 29 of paper or like fibrous material which is preferably porous and possesses other desired properties.- .The fibrous body of the blank is preferably coated or impregnated with a material indicated by reference numeral 30 which will change its color upon exposure to an electric potential or passage of an electric current. Such color changing substances, for example, are lead thiosulphate; a material having a plurality of allotropic forms such as mercuric sulphide, mercuric iodide, or mercuric oxide; and lead thiocyanate. The blank which has been coated or impregnated with a color changing material such as one of those disclosed, is rendered conducting by moistening it with an alcohol after a certain desired alcohol soluble salt is applied.

Salts of sodium, potassium, and ammonium, preferably their iodides, sulpho-cyanides, bromides, chlorides and nitrates, form conductive solutions in alcohols. Other inorganic salts and organic compounds are also conductive in nonaqueous solution and their use in the manner disclosed is within the scope of thepresent invention. We have discovered that the solubility of the salts enumerated. above can be employed in preparing a recording paper which can be made conductive without moistening the paper with water, as the solubility of these salts in a volatile solvent such as an alcohol, makes possible their use.

Depending upon the circumstances encountered when a record is to be made'in practicing the invention, an alcohol may be selected from that fire and explosion hazards are eliminated,

and a minimum of residual odor. In general, for higher recording speeds, alcohols of higher evaporation rate are preferred.

Suitable alcohols, for example, are normal butyl, normal propyl, iso-butyl and iso-propyl alcohols. Other suitable alcohols are amyl alcohol and higher alcohols, although their sol-vent action becomes less on the salts preferred.

Methyl or ethyl alcohols which are highly volatile may be also mixed for use with any,of the alcohols mentioned above.

The corresponding ketones, aldehydes and mono-substituted esters of di-hydric alcohols also are available as solvents for the salts above referred to.

In practicing the invention either of two methods, equally satisfactory, may be followed. v The body 29 of the blank may first be impregnated with any one of the salts named above either during manufacture or after manufacture in a water or alcohol solution. Before or after this impregnation with any one of the desired salts, and preferably before -their application, a color changing material is put in or upon the fibrous body 29. The recording blank thus prepared is dry, may be readily handled, and is ready for use in a facsimile or other recorder provided with suitable moistening means.

The second method of preparing a blank is to have the body 28 provided with the color changing material. If the color changing mate'- that it will remain upon the saidb ody and resist removal by the alcohol. The blank 28 thus treated with the color changing material is used on the recorder and a solution of one of the above named electrolytes in one 'of the enumerated alcohols or alcohol derivative is applied locally ahead of the stylus as by the absorbent wick 22.

In operation of the recorder, the reservoir 24 is provided with a quantity of desired solvent or, if the second method of practicing the invention is used, with a solution of the desired salt in any one of the alcohols stated to be suitable. The pad or wick 22 can be of very small area and is placed in such a manner that the surface of the blank is moistened only sufficiently in ad- Vance of the stylus so that the salt will enter into solution as the recording proceeds. The readily volatile solvent evaporates, leaving the blank dry shortly thereafter. At no time is the blank or any part thereof soggy and weakened in The liquid, however, is applied to' the differs from that of Fig. l inasmuch as the absorbent member 22 is omitted. Application of the liquid is accomplished by means of a capillary tube3-l. This capillary tube extends into the closed reservoir 32 which is in communication through-the conduit '33 with a source of fluid under pressure such as an air' compressor to assist in ejecting the contents of the reservoir 32 through the relatively minute opening in the capillary tube 3|. If the internal passage in the tube 3| may rest lightly in contact with the reservoir'32 may be open, in which case tube 3| will act as a syphon and deposit a supply of liquid continuously upon the record surface. The tube 3t may rest lightly in contact with the surface of the recording blank upon the cylinder I0 or it may be spaced slightly therefrom as shown so that the solvent is applied in the form of a very fine stream or spray.

The operation of this embodiment will be readily understood from the foregoing description of the structure andoperation of the apparatus disclosed in Fig; 1.

Figs. 3, 4 and 5 of the drawing show a receiving apparatus of the continuous type in which the blank is in the form of a continuous web or sheet 34. The said web or sheet is prepared for use in the recorder in accordance with the procedure outlined above in. connection with the description of the blank 28. The web 34 is curved at the point where the record is impressed upon it to permit thereon operation of a revolving stylus or a plurality of stylii 35, which is energized in accordance with the received signals and vided with a series .of apertures 39 to permit escape of fluid from the interior of the pipe into a pad or block ll of suitable absorbent material. The block of absorbent material 40 is held in contact with the pipe 38 opposite the series of openings 39 by means such as the clips 4| which firmly engage the pad 40 but permit its removal and replacement when desired. The interior of the pipe or conduit 38 is in communication with a reservoir 42, which is preferably of the kind described in connection with Fig. 2,

whereby fluid may be ejected into the pad 40' under pressure insuring an equal distribution of the fluid over the surface of the curved web 34. It is to be noted that the pad 40 may serve as a guide for the paper web 34 to assist in giving it a curved form so that it will present every part of its surface to action of the stylus 35. It will be understood that the absorbent material represented by the pad 40 in Fig. 3 may be in contact with the record blank on the surface thereof. contacted by the stylus or on the side opposite the stylus as shown.

From the foregoing complete disclosure of the invention in its several aspects, it will be seen that there is provided a recording method and means which permits simplification of the moistening apparatus and recorder and also avoids all objectionable features of prior recording methods and apparatus wherein it is necessary to saturate the body of the recording blank with water or aqueous solutions.

The nature of the invention will be deter-' mined from the foregoing and the scope thereof is defined in the appended claims.

We claim:

1. A recording blank comprising a sheet of fibrous material, an adherent coating on said sheet of a recording substance which has the property of being marked by passage of electric current through the coating, and a substance which forms an electrolyte when dissolved in a non-aqueous solvent, distributed in the body of said sheet- 2. The method of recording telegraphic signals which comprises applying as a coating to a record blank a quantity of material adapted to be marked upon passage of an electric current through said c0atinx. adding a quantity 'of a dry electrolyte soluble in a non-aqueous solvent to the blank and during recording applying a nonaqueous solvent to said blank and thereafter selectively passing an electrical current through elemental areas of said coated blank.

3. The method of recording telegraphic signals which comprises applying to a record blank a quantity of material which has the property of being marked by passage of electric current therethrough uniformly distributed over the sur- !ace 0! said blmk, distributing through the body of said blank a quantity of a dry electrolyte soluble in a highly volatile non-aqueous solvent and during recording applying said solvent to successive limited areas of said blank and thereafter selectively passing an electrical current through the limited areas of said blank.

4. The method of recording telegraphic signals which comprises applying to a record blank a coating of a quantity of a material which has the property of being marked by passage of electric current therethrough and during recording selectively applying a non-aqueous elec trically conducting solution of a salt to elemental areas of the blank and thereafter passing an electrical current through said elemental areas of said blank.

5. The method of recording telegraphic signals which comprises applying to a record blank a quantity of material-which has the property of being marked by passage of electric current therethrough uniformly distributed over the surface of said blank and during recording selectively applying a non-aqueous electrically conducting solution of a salt to successive elemental areas of said blank and thereafter passing an electrical current through said elemental areas of said blank.

6. A recording blank comprising a support, said support bearing a recording medium adapted to be marked by the passage of .electric current through the blank and being impregnated with a material having the property of conducting electricity upon moistening with a non-aqueous I solvent.

7. A recording blank comprising a sheet of fibrous material, an adherent coating substance adapted to be marked by passage oi current through said blank on said sheet, and sodium nitrate distributed in the body of said sheet whereby said sheet is rendered electrically conductive upon application of an alcohol thereto.

8. A recording blank comprising a sheet of fibrous material, an adherent coating substance adapted to be marked by passage of current through said blank on said sheet, and ammonium nitrate distributed in the body of said sheet whereby said sheet is rendered electrically conductive upon application of an alcohol thereto.

9. A recording blank comprising a sheet of fibrous material. an adherent coating substance adapted to be marked by passage of current through said blank on said sheet, and a dry electrolyte soluble in an alcohol distributed in the body of said sheet whereby said sheet is rendered electrically conductive upon application of an alcohol thereto. a

' BERNARD L. KLINE.

ROBERT D. PARRO'IT. GEORGE L. ERICKSON. 

